https://ph02.tci-thaijo.org/index.php/TJOR/issue/feed Thai Journal of Operations Reseach : TJOR 2019-12-24T08:54:49+07:00 Associate Prof Dr.Kannapha Amaruchkul orjournal.th@gmail.com Open Journal Systems วารสารไทยการวิจัยดำเนิงาน https://ph02.tci-thaijo.org/index.php/TJOR/article/view/177857 Simulated Annealing for the Route Planning of Advisors in the RMUTL Cooperative Education Program 2019-09-17T07:28:40+07:00 Parida Jewpanya parida.jewpanya@gmail.com <p>The Rajamangala University of Technology Lanna (RMUTL) is Thailand's leading university in the field of science and technology. The university focuses on producing graduates who are ready for workplaces through a hands-on learning system. RMUTL incorporates a Cooperative Education Program (CO-OP) in the learning system which aims to gives students an opportunity to receive career training in industries. The students in the final academic year are required to attain this program for a semester to be prepared for the workplace. During the students’ internship period, the RMUTL CO-OP has a team of advisors who need to visit those students in the industries at least two times to give the students advice on their projects and working life. The current visiting plan is created based on the planner experience which sometimes ineffective in term of costs. Therefore, in this study, a mixed-integer linear programming model is formulated to help the planner find an optimal route for the advisors. The objective is to minimize the total cost of the advisor's visitation.&nbsp; Moreover, we propose a simulated annealing heuristic (SA) to solve the problem. We generate benchmark instances and solved them by SA. Computational results show the excellent performance of SA in terms of solution quality and computational efficiency.</p> 2019-09-17T07:28:19+07:00 Copyright (c) 2019 Thai Journal of Operations Reseach : TJOR https://ph02.tci-thaijo.org/index.php/TJOR/article/view/195475 The Prediction of Surface Roughness in the S45C Medium Carbon Steel Turning Process by Using Response Surface Methodology 2019-12-24T08:54:18+07:00 Pongthorn Ruksorn pongthornruksorn@gmail.com <p>S45C medium carbon steel is increasing on demand due to it has been applied in various fields. The objective of the research was to study appropriate setting of parameters and the regression model for surface roughness prediction in the S45C Medium Carbon Steel Turning Process by using Box-Behnken experimental design. Three control factors were investigated including cutting speed, feed rate and depth of cut. The results indicated that the appropriate setting to minimize the surface roughness were cutting speed at 300 meter per minute, feed rate at 0.20 millimeter per round, depth of cut at 0.10 millimeter. The appropriate setting produced the surface roughness of 0.5477 micrometer and the composite desirability equals 0.98911.</p> 2019-12-24T08:54:16+07:00 Copyright (c) 2019 Thai Journal of Operations Reseach : TJOR https://ph02.tci-thaijo.org/index.php/TJOR/article/view/207146 Nurse scheduling model by integer linear programming (A case study : The Fort Sunpasitthiprasong hospital) 2019-12-24T08:54:34+07:00 Ratee Bojaras ratee.b@ubu.ac.th <p>In this research, we formulate the model of nurse scheduling by using integer linear programming (A case study: The Fort Sunpasitthiprasong hospital). The objectives of the model are to maximize the number of nurse s’day-offs subject to the hospital’s rules with Lingo and compare to the head of nurse manually. The results show an effective scheduling because it satisfied all of the hospital’s rules with the maximum of nurse s’day-offs.</p> <p><strong>&nbsp;</strong></p> 2019-12-24T08:54:31+07:00 Copyright (c) 2019 Thai Journal of Operations Reseach : TJOR https://ph02.tci-thaijo.org/index.php/TJOR/article/view/203724 Location of Infectious Waste Incinerator of the Hospital in Maha Sarakham Province 2019-12-24T08:54:49+07:00 Rojanee Homchalee rojanee.h@msu.ac.th <p>This research aims to develop mathematical model for locating the infectious waste incinerator for 13 hospitals in Maha Sarakham province. Mathematical model was developed as a Goal Programming with three goals, minimizing the total cost, minimizing the total distance between hospitals and the location of infectious waste incinerator, and minimizing the number of location of infectious waste incinerator. This mathematical model was solved by LINGO. The result showed that there were two locations of infectious waste incinerator in Mahasarakham hospital and Nadun hospital with capacity of 1,200 and 400 kg/day, respectively. The total cost is minimized to 16,108 baht/day. Additionally, infectious waste was transported from Mahasarakham hospital, Borabue hospital, Kosum Phisai hospital, Chiang Yuen hospital, Kae Dam hospital, Kantharawichai hospital, Kut Rang hospital, and Chuenchom hospital to incinerator located in Mahasarakham hospital, with the total amount of 1,030.11 kg/day. Moreover, infectious waste was transported from Nadun hospital, Phayakkhaphum Phisai hospital, Wapi Pathum hospital, Na Chueak hospital, and Yang Si Surat hospital to incinerator located in Nadun hospital, with the total amount of 180.17 kg/day.</p> 2019-12-24T08:54:47+07:00 Copyright (c) 2019 Thai Journal of Operations Reseach : TJOR